Felting needle

ABSTRACT

A felting needle is disclosed in which the barb grooves have a rounded roof and a flat throat thereby providing a stronger needle blade for a given fiber capacity. The groove configuration permits economies in the manufacture and maintenance of tooling.

O United States Patent [111 3,762,004 Shepard et al. 1 Oct. 2, 1973 [54] FELTING NEEDLE 3,432,896 3/1969 Meagher 28/4 N [751 Richard Shepard: MM 3131232 311333 lfiiiifiii: ..:::1 $3112 Ashmead, both of Torrington, Conn.

[73] Asslgneez gj z xg gg g Primary ExaminerLouis K. Rimrodt g Att0mey--Frank s. Troidl et al. [22] Filed: Jan. 14, 1972 [21] Appl. No.2 217,887

[57] ABSTRACT [52 U.S. Cl 23/4 N A felting needle is disclosed in which the barb grooves [51] '3" Cl D04! 18/00 have a rounded roof and a flat throat thereby providing [58] Fleld of Search 28/4 N a stronger needle blade for a given fiber p y The groove configuration permits economies in the manu- [56] Reierences cued facture and maintenance of tooling.

UNITED STATES PATENTS 3/1967 Foster 28/4 N 5 Claims, 7 Drawing Figures PATENTEU 4 W973 3,762,004

FELTING NEEDLE This invention relates to felting needles; more particularly, this invention is a new configuration of felting barbs which provides a stronger needle and economy in tool maintenance.

In the felting process, needles having downwardly directed barbs are pushed through matted fibers to carry them through a base fabric. When retracted, the needles release, the matted fibers which remain in the fabric, and the cycle is repeated to produce a felt. The blade of a felting needle is generally triangular in cross section and the barbs are made by forcing a chisel into the apices of the blade. Flat chisels produced straight edged barbs which tended to cut the materials. This was both wasteful of fiber and produced an inferior felt. The problem was solved by producing grooves with rounded roofs and throats. However, for a given fiber capacity, the grooves had to be indented more deeply, resulting in a weaker needle, and the curvature of both roof and throat required tooling with aligned recesses, thus, the tooling was expensive both as to initial cost and as to maintenance.

Since the pulling force on the fiber is generated entirely at the roof of the groove, our needle is provided with a rounded roof and a flat throat. This results in a stronger needle and economies of manufacture and tooling maintenance.

The features and advantages of our invention may be more readily understood by reference to the drawings in which:

FIG. 1 is a partial elevation of a felting needle showing a barb;

FIG. 2 is a cross section of a needle taken through the barb in FIG. 1 along line 2-2;

FIG. 3 is an elevational partial section of a tool for making a felting needle barb;

FIG. 4 is an end view of the tool of FIG. 3;

FIGS. 5 and 6 are partial sections of other embodiments of the tool in FIG. 3; and

FIG. 7 illustrates the position of two tools during lapping of the curve shown in FIG. 3.

Like parts throughout the various views are referred to by like number.

Referring to the drawings, and particularly to FIG. 1-, a felting needle 10 has a barb 12 and a groove 14 which is defined by a throat l6 and a roof 18. FIG. 2 is a cross section taken through the barb and shows that the throat is a fiat surface whereas the roof is rounded. In our needle the groove depth 20 need not be as great as in needles made according to prior art (wherein both roof and throat are rounded) to give the same fiber capacity, and a stronger needle blade results. To prevent wedging of fiber, the root 22 of the groove is curved to present a concave surface to the fibers.

The barb is created by forcing a chisel-shaped tool 24 into the needle blade. The tool has a recess 26 ground into its leading face 28 as illustrated in FIGS. 3 and 4 to form the curved roof 18. The recess and the base of the tool 30 intersect in a curve 32 which forms the root 22 of the needle groove. This curve 32 may be tangent to either or both the base of the recess 26 and the base of the tool 30 as shown in FIGS. 3, 5, and 6. As the tool wears, it is a simple matter to grind the base flat to line 34 and lap a new radius 36 for forming the root 22. When a curve is tangent to the recess and perpendicular to the base as illustrated in FIG. 3, two tools 24 and 38 may be lapped simultaneously by abutting the tool bases and running a lap through their recesses. This method is depicted in FIG. 7 and permits economies in manufacture and maintenance of the tools.

We claim:

1. A felting needle comprising a body having at least one barb, the barb projecting from the body at an angle from the longitudinal axis of the needle thereby forming a material engaging groove between the barb and the body, the body portion of the groove being defined as the throat of the groove and the barb portion defined as the roof, the roof being a convex surface and the throat being a flat surface.

2. The felting needle of claim 1 having a plurality of barbs.

3. The felting needle of claim 2 wherein the intersection of the throat and roof is a curve tangent to both the roof and the throat.

4. The felting needle of claim 2, wherein the intersection of the throat and the roof is a curve tangent to the roof and perpendicular to the throat.

5. The felting needle of claim 2 wherein the intersection of the throat and roof is a curve tangent to the throat and perpendicular to the roof.

. i III 'II 

1. A felting needle comprising a body having at least one barb, the barb projecting from the body at an angle from the longitudinal axis of the needle thereby forming a material engaging groove between the barb and the body, the body portion of the groove being defined as the throat of the groove and the barb portion defined as the roof, the roof being a convex surface and the throat being a flat surface.
 2. The felting needle of claim 1 having a plurality of barbs.
 3. The felting needle of claim 2 wherein the intersection of the throat and roof is a curve tangent to both the roof and the throat.
 4. The felting needle of claim 2, wherein the intersection of the throat and the roof is a curve tangent to the roof and perpendicular to the throat.
 5. The felting needle of claim 2 wherein the intersection of the throat and roof is a curve tangent to the throat and perpendicular to the roof. 